geographic data and leaflet.js
DESCRIPTION
Learn about geographic data and web mapping using the Leaflet.JS library. From a talk given at the Fall 2014 hack@uchicago Hackathon given at the UChicago Computation Institute.TRANSCRIPT
Geographic Data and Leaflet.jsFall 2015 hack@uchicago Hackathon
Web mapping toolsdemocratize spatial
knowledge
WhereWeWalkhttps://github.com/manleyjster/wherewewalk
LargeLots.comhttp://largelots.org/
http://datamade.com/
MapKnitterhttp://mapknitter.org/
https://github.com/publiclab/mapknitter
“Maps are often used by those in power to exert influence over territory, or control territorial narratives. "Grassroots mapping" attempts to invert this dynamic by using maps as a mode of communication and as evidence for an alternative, community-owned definition of a territory.”
http://publiclab.org/wiki/balloon-mapping
iD Editorhttps://www.openstreetmap.org/edithttps://github.com/openstreetmap/iDhttps://www.mapbox.com/osmdev/
Other cool projects
⬝ http://mapmill.org/ - Crowdsourced aerial image processing
⬝ http://www.geograph.org.uk/ - Aims to collect geographically representative photos for every km² in Britain and Ireland
⬝ http://hot.openstreetmap.org/ - OpenStreetMap Humanitarian
In the wild today:Leaflet*mapbox.js*Google Maps JavaScript APIArcGIS API for JavaScriptOpenLayers*d3*mapbox-gl-js*
Challenges in web mapping
⬝ Creating and acquiring map tiles.⬝ Getting data into the browser.⬝ Rendering large vector data sets.
What’s cool about Leaflet?
⬝ Easy to add custom map tiles and data sets⬝ Supports mobile devices⬝ Fast!⬝ Open source⬝ Good maintainers and active development
community
Useful tools for geospatial analysis
⬝ GDAL (Geospatial Data Abstraction Library)⬝ includes command line tool ogr2ogr, useful for
converting between vector formats.⬝ QGIS
⬝ Full-featured GIS software with GUI
Try it out
1 git clone https://github.com/manleyjster/gentrifoo2 cd gentrifoo3 npm install4 git checkout -b <your-name>5 npm start
Chicago Data Portal - Building Footprints Data Sethttp://bit.ly/1Bsoyaf
+ ++Building footprints
Bin building stories by census tract
Bin building construction year by census tract
Add something
1. Add a panel to the map to show additional data from the GeoJSON file when the user hovers over a census tract.
2. Add a slider so that the user can advance time forwards and backwards. 3. Improve the property deterioration model - make the condition of
properties in each census tract depend on the conditions in neighboring census tracts. (Make use of the spatial indexing of the RTree that is built in to the GentrificationModel).
http://leafletjs.com/reference.html
justinmanley.io@outoftheyards
Justin [email protected]